import json

# 将变量名 str 替换为 json_str
json_str = {"createBy": null,         "createTime": null,         "updateBy": null,         "updateTime": null,         "remark": null,
            "id": 27854,         "oldId": null,         "userId": 184,         "questionIdList": null,         "type": 5,         "difficulty": 2}

try:
    data = json.loads(json_str)
    print(data)
except json.JSONDecodeError as e:
    print(f"解析错误: {e}")
